Cuspate forelands, also known as cuspate barriers or nesses in Britain, are geographical features found on coastlines and lakeshores that are created primarily by longshore drift. Formed by accretion and progradation of sand and shingle, they extend outwards from the shoreline in a triangular shape. Some cuspate forelands may be stabilised by vegetation, while others may migrate down the shoreline. Because some cuspate forelands provide an important habitat for many flora and fauna, effective management is required to reduce the impacts from both human activities and physical factors such as climate change and sea level rise.
The debate involving how cuspate forelands form is ongoing. However, the most widely accepted process of formation involves long shore drift. Where longshore drift occurs in opposite directions, two spits merge into a triangular protrusion along a coastline or lakeshore. Their formation is also dependent on dominant and prevailing winds working in opposite directions. Formation can also occur when waves are diffracted around a barrier.
Cuspate forelands can form both along coastlines and along lakeshores. Those formed along coastlines can be in the lee of an offshore island, along a coastline that has no islands in the vicinity, or at a stream mouth where disposition occurs.
A cuspate foreland can form in a strait or along a coastline that has no islands or shoals in the area. In this case, longshore drift as well as prevailing wind and waves bring sediment together from opposite directions. If there is a large angle between the waves and the shoreline, the sediment converges, accumulates, and forms beach ridges. Over time, a cuspate foreland forms as a result of continued accretion and progradation. An example of this type of cuspate foreland is the one found at Dungeness along the southern coast of Britain. This cuspate foreland has formed as a result of the merging of SW waves from the English Channel, and waves from the east from the Strait of Dover. Another example is the cuspate foreland found between Awatere River and White Bluffs in Marlborough, New Zealand. This foreland has ridges on the eastern and northern sides which face the prominent waves.
In other circumstances, spits are formed when long shore drift moves beach material down the beach until the coastline makes an abrupt change in direction, leading to the beach material 'spilling over' the corner to create a protrusion. This normally occurs across a river mouth. In the case of a cuspate foreland, the prevailing wind and a powerful secondary wind in the opposite direction move shingle down the coastline from both directions to a place where the coastline changes, causing a foreland to develop. The majority of cuspate forelands are formed over a coastline that juts out into the sea at enough of an angle to allow the drifting beach material to 'spill over' as a result of long shore drift in both directions.
A cuspate foreland can form in the lee of an island. In this case, oncoming waves are diffracted around the island, protecting the coastline from the oncoming wave fronts. Sediments brought along the shoreline via longshore drift are then able to settle and accumulate in the lee of the island where there is less wave energy. This type of foreland has formed on the west shore of the North Island of New Zealand, in the lee of Kapiti Island. Waves refract around Kapiti Island, forming an area of low wave energy where sediment from the Waikanae River is able to settle. There is uncertainty whether the cuspate foreland has formed as a result of sediments coming from the north via longshore drift, or whether it has formed as a result of a complex cycle of sediments moving out to the continental shelf and then back again.
As well as forming along coastlines, cuspate forelands can also form along lake shores, although less is known about this type of cuspate foreland. This type of cuspate foreland includes Point Pelee along the shoreline of Lake Erie, and those found along the shoreline of Lake Victoria in Australia. There are two theories with regard to the formation of Point Pelee. Firstly, it is thought that Point Pelee has formed from depositional processes. Alternatively, it is suggested that Point Pelee is a relic of a past feature that has eroded over time. This gap in knowledge provides the opportunity for further research. It is likely that Point Pelee is migrating westwards since accretion is occurring on the western side, and erosion is occurring on the eastern side. Lake Victoria in Australia also has a number of cuspate forelands. Point Scott is a cuspate foreland along this lakeshore that has formed from the gradual accumulation of sand and gravel.
Cuspate forelands can be separated into three distinct areas: the central nose or apex, and two marginal wings. The apex usually has ridges that run parallel to the converging shorelines. Cuspate forelands can extend up to 5 km from the shoreline, and an underwater shoal may extend much further, up to 15 km from the exposed apex. Located between the mainland and the foreland are often lagoons or marshy areas. In some areas, such as along the North Carolina coastline, a series of cuspate forelands may form at least 100 km apart. In areas that have a large amount of shingle, such as the cuspate foreland at Dungeness, it is also common for a fresh water table to be present.
Once formed, cuspate forelands can remain where they are and continue to develop as sediment accumulates, or alternatively they may migrate down the coast as one side of the foreland erodes and the other side accretes. Cuspate Forelands that move are typical of those that are formed on open coastlines. The direction of migration is often indicated by a series of successive beach ridges on the advancing side of the foreland where there is less wave energy. The movement of cuspate forelands is commonly explained by longshore drift acting as the main process. However, there have been observed cases where two cuspate forelands on the same shoreline have migrated in opposite directions, showing that longshore drift does not always provide a sufficient explanation for their migration.
If there is an offshore sandbank present, the position of the cuspate foreland is usually related to its position. If there is a change in the position of the sandbank, the position of the cuspate foreland typically follows. Not only does the sandbank act like an island since it causes waves to refract around it, but it also provides a source of sediment. As sand erodes from the sandbank, it is pushed towards the coastline, contributing to the formation of the cuspate foreland as the sandbank migrates along the coast. This often occurs in the opposite direction to longshore drift.
In the case of a cuspate foreland that has formed close to an island, it is possible for it to extend right up to the island, forming a tombolo. Depending on the physical conditions such as storms, the feature can alternate between a cuspate foreland and a tombolo. Gabo Island in South Australia is an example of where this occurs.
After the formation of the cuspate foreland into its distinctive triangular shape, it will start to be colonised by pioneer species that are hardy and tough enough to survive in the environment. These pioneer species secure the cuspate foreland and allow a greater amount of sediment to further secure it. Colonization and succession of vegetation is dependent on a number of factors. Firstly, if the shingle is too coarse, the amount of fine sediment that can remain between the spaces is reduced, and the likelihood that seeds will germinate and grow upwards is low. Seeds will also fail to germinate and grow if there is insufficient retention of fresh water. Stable cuspate forelands that are composed of shingle often have vegetation above the high tide line. As vegetation is established, mites and collembolans break down plant matter such as roots, resulting in the accumulation of organic matter. Plants also cause the soil to develop and water retention to increase, therefore providing a habitat where more plants can grow. Vegetation above the high tide line is common on cuspate forelands that are stable and composed of shingle.
Cuspate forelands provide a habitat for various flora and fauna. If a foreland is relatively stable and experiences low wave impact, it may be possible for vegetation to grow. In the United Kingdom, 11 taxa of invertebrates are found on shingle habitats. Shingle beaches also provide a habitat for birds to breed, nest, and rest en route while migrating.
There are different management issues with regard to cuspate forelands depending on their formation. If a cuspate foreland has formed from deposition, it may be vulnerable if human interference alters the transport of sediments from the shoreline. However, if the cuspate foreland is a relic of a past feature that has eroded, human interference with longshore sediment movement will not have a significant impact on the cuspate foreland. For a cuspate foreland to be maintained, the input of sediment must be greater than output of sediment. Activities such as coastal development or engineering must be regulated for sediment to continue moving towards the foreland where it can be deposited. Development along cuspate forelands is risky due to erosion and the vulnerability to storms and sea level rise. As sea levels rise, cuspate forelands are likely to be at risk as they could move inland.
At Point Pelee, approximately 1,900 hectares of former agricultural land on the cuspate foreland is now under water as a result of wind erosion and compaction of organic soils on the foreland. This foreland is particularly vulnerable to erosion when high lake levels are combined with spring and autumn cyclonic activity. Erosion can also occur as spring storms cause ice to scour the lake bottom at the edge of the foreland. Because there is uncertainty about its formation, there is uncertainty with regard to management, although Parks Canada realises the importance of including Point Pelee National Park in management plans.
The management of coastlines needs to take into account the natural processes that occur on cuspate forelands since many provide a habitat for birds. Alternative ways of managing coastal erosion is needed, such as the use of ‘soft’ defences instead of high impact defences such as sea walls. Some cuspate forelands naturally do not contain any vegetation due to a high level of disturbance from physical factors such as wave action. However, with the frequency of storms arising from climate change, the effect on forelands and their associated vegetation needs to be effectively managed.
Beach cusps are shoreline formations made up of various grades of sediment in an arc pattern. The horns are made up of coarser material and the embayment contains finer sediment.
They can be found all over the world and are most noticeable on shorelines with coarser sediment such as pebble beaches. However, they can occur with sediment of any size. They nearly always occur in a regular pattern with cusps of equal size and spacing appearing along stretches of the shoreline. These cusps are most often a few metres long. However, they may reach 60 m (200 ft) across. Although the origin of beach cusps has yet to be proven, once cusps have been created they are a self-sustaining formation. This is because when an oncoming wave hits the horn of a beach cusp, it is split and forced into two directions. The crashing of the wave into the cusps slows its velocity, causing coarser sediment to fall out of suspension and be deposited on the horns. The waves then flow along the embayments (picking up finer sediment) and run into one another in the middle. After this collision these waves attempt to flow back out to sea where they are met by incoming waves. Therefore, once the cusp is established, coarser sediment is constantly being deposited on the horn and finer sediment is being eroded away from the embayments. This process causes the horners and embayments to at least maintain their size, if not grow larger.Cape Banks
Cape Banks is a headland in the Australian state of South Australia located in the gazetted locality of Carpenter Rocks at the south end of Bucks Bay and the north end of Bungaloo Bay on the state's south east coast about 36 kilometres (22 miles) west south west of the city of Mount Gambier.The cape is described by one source as being "a rocky point, 15 metres (49 feet) high, 24 nautical miles (44 kilometres; 28 miles) SSE of Cape Buffon" while another source describes it as ‘a cuspate foreland protruding 500 metres (1,600 feet) seaward in lee of calcarenite rocks and reefs’.It was named by the Royal Navy officer, James Grant, on 3 December 1800.The navigation aid known as the Cape Banks Lighthouse is not located on the cape but on an unnamed headland located at the northern end of Lighhouse Bay which is the next bay to the north-west of Bucks Bay.Cape Santo André
Cape Santo André (Portuguese for Saint Andrew) is a cape located in the Northern coast of continental Portugal, in Santo André, municipality of Póvoa de Varzim. It is the tip of Póvoa de Varzim's cuspate foreland.
It is probably the old Roman Avarius, Auarius Promontorium or Auaron Promontorium (In Ancient Greek, Αὔαρον ἄκρον) referred by Ptolemy, geographer of Ancient Greece, in the territory of the Callaici Bracares, between the river Avus (Ave River) and river Nebis (Neiva River).Coast
The coast, also known as the coastline or seashore, is the area where land meets the sea or ocean, or a line that forms the boundary between the land and the ocean or a lake. A precise line that can be called a coastline cannot be determined due to the coastline paradox.
The term coastal zone is a region where interaction of the sea and land processes occurs. Both the terms coast and coastal are often used to describe a geographic location or region (e.g., New Zealand's West Coast, or the East and West Coasts of the United States). Edinburgh is an example city on the coast of Great Britain.
The term pelagic coast refers to a coast that fronts the open ocean, as opposed to a more sheltered coast in a gulf or bay. A shore, on the other hand, can refer to parts of land adjoining any large body of water, including oceans (seashore) and lakes (lake shore). Similarly, the somewhat related term stream bed or stream bank refers to the land alongside or sloping down to a river (riverbank) or body of water smaller than a lake. Bank is also used in some parts of the world to refer to an artificial ridge of earth intended to retain the water of a river or pond; in other places this may be called a levee.
While many scientific experts might agree on a common definition of the term coast, the delineation of the extents of a coast differ according to jurisdiction, with many scientific and government authorities in various countries differing for economic and social policy reasons. According to the UN atlas, 44% of people live within 150 km (93 mi) of the sea.Coastal geography
Coastal geography is the study of the constantly changing region between the ocean and the land, incorporating both the physical geography (i.e. coastal geomorphology, geology and oceanography) and the human geography (sociology and history) of the coast. It includes understanding coastal weathering processes, particularly wave action, sediment movement and weather, and the ways in which humans interact with the coastCoastal management
Coastal management is defence against flooding and erosion, and techniques that stop erosion to claim lands.Coastal zones occupy less than 15% of the Earth's land area, while they host more than 45% of the world population. Nearly 1.4 billion people live within 100 km of a shoreline and 100 m of sea level, with an average density 3 times higher than the global average for population. With three-quarters of the world population expected to reside in the coastal zone by 2025, human activities originating from this small land area will impose heavy pressure on coasts. Coastal zones contain rich resources to produce goods and services and are home to most commercial and industrial activities.
Protection against rising sea levels in the 21st century is crucial, as sea level rise accelerates. Changes in sea level damage beaches and coastal systems are expected to rise at an increasing rate, causing coastal sediments to be disturbed by tidal energy.Dungeness (headland)
Dungeness (UK: ) is a headland on the coast of Kent, England, formed largely of a shingle beach in the form of a cuspate foreland. It shelters a large area of low-lying land, Romney Marsh. Dungeness spans Dungeness Nuclear Power Station, the hamlet of Dungeness, and an ecological site at the same location. It lies within the civil parish of Lydd.Island
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island in a river or a lake island may be called an eyot or ait, and a small island off the coast may be called a holm. A grouping of geographically or geologically related islands is called an archipelago, such as the Philippines.
An island may be described as such, despite the presence of an artificial land bridge; examples are Singapore and its causeway, and the various Dutch delta islands, such as IJsselmonde. Some places may even retain "island" in their names for historical reasons after being connected to a larger landmass by a land bridge or landfill, such as Coney Island and Coronado Island, though these are, strictly speaking, tied islands. Conversely, when a piece of land is separated from the mainland by a man-made canal, for example the Peloponnese by the Corinth Canal or Marble Hill in northern Manhattan during the time between the building of the United States Ship Canal and the filling-in of the Harlem River which surrounded the area, it is generally not considered an island.
There are two main types of islands in the sea: continental and oceanic. There are also artificial islands.Kayak Point County Park
Kayak Point County Park is a county park near Warm Beach, in Snohomish County, Washington. The 670-acre (270 ha) park is located along Port Susan and includes a saltwater beach, a boat launch, a golf course, and public campgrounds. Kayak Point is the most popular county park in Snohomish County, and is mainly visited for recreational fishing, crabbing, and birdwatching.
Kayak Point was home to a private, locally-run seaside resort from the 1920s to 1950s, named after a pair of Inuit kayaks brought to the resort from Alaska. In the 1960s, Atlantic Richfield proposed construction of an oil refinery at Kayak Point, purchasing 1,200 acres (490 ha) of land, and received approval from the county to re-zone the area for industrial use. Local residents opposed the refinery during public hearings and later filed a lawsuit against the county over its re-zoning decision, which was voided by the Washington Supreme Court in 1979 as an inequitable use of "spot zoning". Atlantic Richfield later attempted to develop some of its land holdings into a master-planned residential community in the 1970s, but failed to receive county approval due to a lack of good roads and sewers. The county park was established in 1972, using waterfront property bought by the county government from Atlantic Richfield.List of landforms
Landforms are categorised by characteristic physical attributes such as elevation, slope, orientation, rock exposure, and soil type.List of places of interest in Suffolk
This is a list of places of interest in the British county of Suffolk. See List of places in Suffolk for a list of settlements in Suffolk.Lydd Airport
Lydd Airport (IATA: LYX, ICAO: EGMD) is located 1.2 NM (2.2 km; 1.4 mi) northeast of the town of Lydd and 12 NM (22 km; 14 mi) south of Ashford in the district of Folkestone and Hythe within Kent, England. Originally named Lydd Ferryfield, it is now also known as London Ashford Airport, although it is over 73 mi (117 km) from central London, and
the name officially refers only to its operator. The airport is operated by London Ashford Airport Ltd, a company ultimately controlled by the Saudi Arabian businessman Sheikh Fahad al-Athel.Lydd Airport has a CAA Ordinary Licence (Number P858) that allows flights for the public transport of passengers or for flying instruction as authorised by the licensee (London Ashford Airport Limited). The airport is currently able to handle aircraft up to the size of a Boeing 737 or Airbus A319, but the runway length means that such aircraft can only take off with a restricted payload. Lydd Air is based at the airport, and it had offered regular flights to Le Touquet Airport in northern France, a service which ended in December 2018.The airport lies adjacent to the unique landscape of Dungeness, a Cuspate foreland that is one of the largest expanses of shingle beach in Europe and which is of international conservation importance for its geomorphology, plant and invertebrate communities and birdlife, a fact that is recognised by its designations as a national nature reserve, a Special Protection Area, a Special Area of Conservation and part of the Site of Special Scientific Interest of Dungeness, Romney Marsh and Rye Bay. This proximity has led to opposition to plans to expand the airport, but the airport has now been granted permission to build a 294 m (965 ft) runway extension and a new terminal building. This will allow it to handle fully loaded Boeing 737 or Airbus A319 aircraft.PPR (Prior Permission Required) must be obtained in order to land.Mudflat
Mudflats or mud flats, also known as tidal flats, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A recent global analysis suggested they are as extensive globally as mangroves. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries. Mudflats may be viewed geologically as exposed layers of bay mud, resulting from deposition of estuarine silts, clays and marine animal detritus. Most of the sediment within a mudflat is within the intertidal zone, and thus the flat is submerged and exposed approximately twice daily.
In the past tidal flats were considered unhealthy, economically unimportant areas and were often dredged and developed into agricultural land. Several especially shallow mudflat areas, such as the Wadden Sea, are now popular among those practising the sport of mudflat hiking.
On the Baltic Sea coast of Germany in places, mudflats are exposed not by tidal action, but by wind-action driving water away from the shallows into the sea. These wind-affected mudflats are called windwatts in German.Orford Ness
Orford Ness is a cuspate foreland shingle spit on the Suffolk coast in Great Britain, linked to the mainland at Aldeburgh and stretching along the coast to Orford and down to North Weir Point, opposite Shingle Street. It is divided from the mainland by the River Alde, and was formed by longshore drift along the coast. The material of the spit comes from places further north, such as Dunwich. Near the middle point of its length, at the foreland point or 'Ness', lies the Orfordness Lighthouse. In the name of the lighthouse (and the radio transmitting station – see below), 'Orfordness' is written as one word.Póvoa de Varzim
Póvoa de Varzim (Portuguese pronunciation: [ˈpɔvu.ɐ ðɨ vɐɾˈzĩ] (listen), locally [ˈpɔβwɐ ðɨ βɐɾˈzĩŋ]) is a Portuguese city in Northern Portugal and sub-region of Greater Porto, 30 km from its city centre. It sits in a sandy coastal plain, a cuspate foreland, halfway between the Minho and Douro rivers. In 2001, there were 63,470 inhabitants, with 42,396 living in the city proper. The city expanded, southwards, to Vila do Conde, and there are about 100,000 inhabitants in the urban area alone. It is the seventh-largest urban agglomeration in Portugal and the third largest in Northern Portugal.
Permanent settlement in Póvoa de Varzim dates back to around four to six thousand years ago; around 900 BC, unrest in the region led to the establishment of Cividade de Terroso, a fortified city, which developed maritime trade routes with the civilizations of classical antiquity. Modern Póvoa de Varzim emerged after the conquest by the Roman Republic of the city by 138 BC; fishing and fish processing units soon developed, which became the foundations of the local economy. By the 11th century, the fishing industry and fertile farmlands were the economic base of a feudal lordship and Varzim was fiercely disputed between the local overlords and the early Portuguese kings, which resulted in the establishment of the present day's municipality in 1308 and being subjugated to monastic power some years later. Póvoa de Varzim's importance reemerged with the Age of Discovery due to its shipbuilders and merchants proficiency and wealth, who traded around the globe in complex trade routes. By the 17th century, the fish processing industry rebounded and, some time later, Póvoa became the dominant fishing port in northern Portugal.Póvoa de Varzim has been a well-known beach resort for over three centuries, the most popular in Northern Portugal, which unfolded an influential literary culture and historical artistic patronage in music and theater. Casino da Póvoa is one of the few and prominent gambling venues in Portugal. Leisure and health benefits provided in large sandy beaches attracts national and international visitors. Póvoa de Varzim holds other landmarks, especially the traditional Junqueira shopping street, Garrett Theatre, the Ethnography and History Museum, Cividade de Terroso, the Medieval Rates Monastery, Baroque Matriz Church, city Hall and Portuguese vernacular architecture in Praça do Almada, and numerous Portuguese cuisine restaurants that make Póvoa de Varzim popular in all Northern Portugal, which started to attract an international following. Farol da Lapa, Farol de Regufe, the main breakwater of the Port of Póvoa de Varzim, Carvalhido and São Félix Hill are preferred for sightseeing. The city has significant textile and food industries. The town has retained a distinct cultural identity and ancient Norse customs such as the writing system of siglas poveiras, the masseira farming technique and festivals.Surf zone
As ocean surface waves come closer to shore they break, forming the foamy, bubbly surface called surf. The region of breaking waves defines the surf zone. After breaking in the surf zone, the waves (now reduced in height) continue to move in, and they run up onto the sloping front of the beach, forming an uprush of water called swash. The water then runs back again as backswash. The nearshore zone where wave water comes onto the beach is the surf zone. The water in the surf zone, or breaker zone, is shallow, usually between 5 and 10 m (16 and 33 ft) deep; this causes the waves to be unstable.Tombolo
A tombolo, from the Italian tombolo, derived from the Latin tumulus, meaning 'mound', and sometimes translated as ayre, is a deposition landform in which an island is attached to the mainland by a narrow piece of land such as a spit or bar. Once attached, the island is then known as a tied island. A tombolo is a sandy isthmus.
Several islands tied together by bars which rise above the water level are called a tombolo cluster. Two or more tombolos may form an enclosure (called a lagoon) that can eventually fill with sediment.Winterton Ness
Winterton Ness is an area of foreland on the North Norfolk coast of England.
Winterton Ness is located to the north of the village of Winterton-on-Sea between grid reference TG489216 in the north to TG506181 to its south. Technically it is a narrow cuspate foreland with a high obtuse angle between its two shorelines. A number of studies appear inconclusive as to the nature if erosion or, conversely, accretion of sediment in the area.
The area was described by Daniel Defoe during the first of his trips for his account A tour thro' the Whole Island of Great Britain.